Method of clearing mine fields



Jan. 6, 1948. B. WALKER ETAL 2,433,875

METHOD OF CLEARING MINE` FIELDS Filed Nov. 16, 1944 E7;' l Elrunk Walker HarnldM-Mnr5E' mafmmvmmd i www Patented Jan. 6, 1948 METHOD OF CLEARING MNE FIELDS Brooks Walker, Piedmont, Calif., and Harol Marston Morse, Princeton, N. J.

Application November I6, 1944, Serial No. 563,742

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 2 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to us of any royalty thereon.

This invention relates to methods of clearing mine fields. A purpose of the invention is to provide an effective means of quickly and safely clearing enemy mine lields by sympathetic detonation of charges.

Another purpose of the invention is to provide a means of carrying said charges to close proximity with said mines to be detonated.

A further purpose is to provide an elective design of charge for the purposes aforesaid.

Other purposes will become apparent from the description of the invention set forth herein.

One method of clearing a path across mine elds is by placing a number of charges in close proximity to the mines and exploding4 the charges. The result is that mines close to the charges may be exploded by sympathetic detonation. In this invention it is proposed to clear a path across a mine field by means of a chain of charges placed across the mine eld the entire chain adapted to be exploded from one end.

In the drawings, Y

Figure 1 is a vertical sectional view of an individual mine exploder,

Figure 2 is a plan view of an individual mine exploder,

Figure 3 is a perspective View of a chain of mine exploders lying across a mine field, showing method of pulling the chain of exploders across the mine fields, the foreground being cut away to show enemy mines beneath the surface, l

Figure 4 is a view of a mine exploder in close proximity to an enemy mine, showing how the charge in the mine exploder is projected into the air and exploded, and

Figure 5 is a perspective' view of an alternate method of getting the mine exploders across the mine eld by shooting a line and pulley across, attached to an anchor.

As shown in Figures 1 and 2 of the drawings, each individual mine exploder is housed in a sheet metal container I with a low center of gravity which is preferably of some well rounded shape such as an oval, with its forward end 2 sloping upward to enable it more easily to slide along the ground and clear obstacles in its path. A loop 3 is fastened to the forward end of the exploder housing I for attaching a rope or cable 4 to it for pulling along the ground.

Another loop 5 is fastened to the rearward end of the exploder housing I for attaching a rope or cable leading to other exploders in the chain to the rear of the individual exploder. Inside the mine there is a container l normally cylindrical in shape, containing a high explosive main charge 8, a booster charge 9 in a central tube I0 in said container l, and a delay charge II in the lower portion of said central tube I8.

A circular, cup shaped base I3 having a peripheral raised portion I4 with an inside diameter only slightly larger than the outside diameter of the container l, is bolted or screwed down to the bottom 21 of the exploder housing I by means of bolts 3l secured through lugs 28 and 29 on base I3. The side walls and top of container I may be of light material such as fibre or sheet metal, but the base 30 of the said container and the base I3 should be of heavy material such as iron inasmuch as the lifting charge I2 is exploded in the cavity between the two bases 30 and I3.

A detonating line 32 made of primacord passes through the mine exploder from front to rear as shown and through a pair of holes 33 and 34 formed in the raised portion I4 of the base I3 and through a diametral channel 35 connecting said two holes. The channel is open at its top between said holes, and crosses through the central Vdepression containing the lifting charge I2.

The delay charge II' is located in a central ver,

tical bore 35 in the base 3U and hence the primacord when detonated will set off both the lifting charge I2 and the delay charge II. The high explosive 8 consists of about 10 pounds of explosive or even more, if desired, to provide a powerful explosion, and the delay charge Il is designed to delay the detonation of the main charge 8, until` the container I has been lifted to a height of about ten feet above the ground where it will have a considerable percussive eiect on the mines in the mine field in the immediate area around the mine exploder, causing them to explode.

As all the mine exploders in the chain are connected together by a primacord 32, it is possible to cause them all to explode by detonating the primacord at either end in the usual manner, by attaching a percussion fuse to the end of the primacord and releasing the striker of the fuse against the percussion cap. The detonator primacord passing through the channel 35, ignites both the lifting charge I2 and the delay charge II. The lifting charge I2 explodes, causing the container 'I to be lifted upwardly, breaking through the top of the mine exploder housing as shown in Fig. 4 and when it reaches the desired height above the ground the main charge 8 explodes, detonating adjacent enemy mines.

In Figure 3, the chain of mine exploders I6, l1, I8 and I9, is hauled across the portion of mine field comprising mines 26, 21, 28 and 29 by means of a rope 2| passing over a pulley 22 attached around a tree trunk 23 by means of a rope 24, tension applied at'y thefend 25":oitheY rope 2l by hand, horse,-or av motor' vehicle;1 serving ton pull the chain of exploders across the mine eld. The pulley 22 having a light rope threaded through it may be carried across the mine field atnight by trained sappers, and the heavyrope2l attached to the light rope and pulled through thepulley 22 when the sapper gets back to his ovvngsideof the mine eld. Where no tree or other xed object is available a hooked v anchor'maybe'used instead. As the mine exploder i1 is set'OfE as shown in Figure 4, the container 1 is thrown into the air, causing the mine 21-to\explode.

Or, as shown in Figure 5, a mortar 31smay be' used to shoot a projectile 38 having a central rod 39 ":rmlyf fastened into the. projectile and having an extensionto Whichareattach'ed-a plurality ofmetal-prongsal forming a'pointed end. vA .pulley 4t isfastenedf tothe extension of the rod 3i!y as shown,.an'd has a light ropeJiZpa'ssed throughi it. The two ends of# the-rope42za'revvvoundA on reels 43 and 44 which arede'signed to'l have Va :minimum of.' friction; so 1 as5 not` toi "impede: the unre'eling of the-rope'llZ; 'The .reelslli` and 44 may be provided With-,any usual device .forupreventing backlash. The projectile' is `provided at fitsllowe'r A end with a propellant vcharge and.' fuse: similar`L tovv those used on mortar shells and' adapted to be ignited by impact against'a 'ring pin inside the mortar barret` inA the vusual manner f when' the `projectile 38 Iisi inserted into' the mortar barrel and allowed to drop-againstthe-'firing pin. The projectile is thus carried' across the mine viield Where its pronged end .forces itself `into the earth. A heavier ropef`2l isattached tonne end-of the light rope l2 andis pulled acrossf through the pulleyflil` by means ofv1 tension on the.r light rope; A chain of mine explod'ers attached -to theendof the heavy lope/ZI i's. then -pulled across the f mineiield as previously described-fand 'shovvn in' Fig'. 3i

'The mine l'ex-pldders' Vmay alternatively be equipped vvi'th`r electric primers and connectedl by electric 'Wirescarrying a current foriv setting them 01T.

I'While theA foregoing specicati'onl sets1 forth the inventionL inspecic'f terms-f it is' to `be understood that fnumerous 'changes in f 'the-shape size, arrangement arid: materials may be'resortedto'without-@departing froni the spirit and' scope-ofthey invention claimedlas`r hereinafter.y

We claim:

1. A device for clearing a path into a field of land mines by exploding the mines in said path, comprising a plurality of individual explosive charges, means for elevating said charges to a predetermined s substantial altitude r above the ground@ fuse means for exploding vsaidfcharges, means for linking said charges together in substantially spaced relationship to form a exible k10 saidiiusesfmeans from a single location whereby all said charges are exploded at substantially the 'Sametime `2. j=Avdevice for clearing a path into a field of land mines by exploding the mines in said path,

comprising' a'plurality of individual explosive charges, explosive means for elevating said charges to a predetermined substantial altitude above the ground,` fuse means for explodingsaid charges; -means- -forl' lin-king'- said charges' together substantially spaeed'relatio'nship to f form a flexible chain of chargesfdravving rneansfor dis'- posingI said' chain-off charges'l iirrtosaid mine: iield, aridAx means* foractuating said' elevating -m'eans and "said *fuse means from f a single location whereby'all` said--charges-are exploded at substantially the same time.

BROOKSWALKER'-, HAROLD MARSTON MORSE.

lrunninENGES CITED '"The'following` references are of record' in the iile of this patent:

l' UNITED? STATES' fPA'TENTS Number d l Name' y Date 275,197v Ggrtilzli'n Api...3',-1883 6243172 Fmiaysonj May..9,1'399 L1,791,716 Davis etal Feb. 1o', 1931 Number Country I ,Date 1 ,28,433 Great Britain. 1'913 OTHER REFERENCES Publication: Popular Science, February 11944,; page-:1119. iBubl-ished :by PopulanScienceBublish- -ngg Cd; Ine-.;1353;Fourth Ave;,fNew-York .10,NL-:Y- 1 Publication vScientifici AmericangiDecernber 

